Does replacing a mains switch, which feeds an existing DB require all circuits to be tested on the DB?

[Tomtom25]

Hi

Ive been tasked with replacing a mains switch, which is fed from the cutout and in turn supplies a domestic DB.

It’s a BS88 switch fuse which I’ll swap like for like, but the existing DB, which is plastic will remain untouched. There will be henley blocks installed between the switch fuse and DB which will then go to a solar inverter.

With replacing the incoming switch fuse, my question is whether is should be testing all circuits from that point or not?

 

[westward10]

Provide an EIC for the switch-fuse only so one circuit. I would also suggest this is notifiable under Part P if it is a dwelling.

 

[ferg]

I would say not as you are not changing the characteristics of the protective device.
If the existing installation looked to be in poor condition then a recommendation for an EICR to be carried out.

 

[pc1966]

Obviously you need to check the means of earthing, Ze, and polarity no matter what for the EIC.

As above, if anything looks dodgy then EICR is a very good suggestion. Even without an EICR being commissioned I would check all of the RCD/RCBO trip-test as an absolute minimum, and check that at least a couple of 13A sockets are OK (polarity and sane Zs) which is minimal effort but allows easier sleep.